I'm not sure if this sort of thing belongs in the client or server side of the RSS model, but I'm starting to get really annoyed with  a few of the planet sites. Subscribing to things like Fedora People and Kernel planet, i'm having to manually mark as read blogs that are syndictated to multiple sites. It would be sweet if liferea could "just know" that I've already read this blog entry, and mark it as read in the other feeds. What do you guys think?